Method for manufacturing drive device, and drive device

Abstract

One end portion of each connector terminal is connected to an end circuit board of an end circuit board assembly. In a first process, a generic circuit board assembly is assembled to a motor frame. In a second process, the end circuit board assembly is assembled to the generic circuit board assembly. In a third process, the other end portion of each connector terminal of the end circuit board assembly is exposed in a mating bore of a corresponding connector, and a connector housing is assembled. The third process is carried out such that a load, which is generated when the other end portion of each connector terminal is exposed in the mating bore of the corresponding connector in the third process, is smaller than a load, which is generated in the first process, and a load, which is generated in the second process.

What is claimed is: 
     
         1 . A method for manufacturing a drive device that includes:
 an electric motor which includes a stator and a rotor;   a controller unit which is placed on one side of the electric motor in an axial direction of the electric motor and is configured to control a drive operation of the electric motor, wherein the electric motor and the controller unit are integrally formed together;   a motor frame that is made of metal and is installed to an end portion of the electric motor which faces the controller unit in the axial direction of the electric motor;   at least two circuit boards, each of which holds at least one electronic component of the controller unit and is stacked at a corresponding one of a plurality of stacking levels on an opposite side of the motor frame which is opposite to the electric motor, wherein the at least two circuit boards include:
 an end circuit board which is farthest from the motor frame among the at least two circuit boards; and 
 at least one generic circuit board which is other than the end circuit board; 
   a connector housing that is made of resin and is shaped in a bottomed tubular form and thereby has:
 a top plate portion which is opposed to the end circuit board; and 
 an outer tubular portion which extends from an outer periphery of the top plate portion toward the electric motor and has an end portion fixed to one of the electric motor and the motor frame, wherein the connector housing has at least one connector, and the at least one connector is formed at the top plate portion and has a mating bore which opens toward a side opposite to the end circuit board; 
   a plurality of inter-board terminals or an inter-board connector, wherein:
 the at least one generic circuit board is only one generic circuit board or at least two generic circuit boards; 
 in one case where the at least one generic circuit board is the only one generic circuit board, the inter-board connector or each corresponding one of the plurality of inter-board terminals is joined between the only one generic circuit board and the end circuit board; and 
 in another case where the at least one generic circuit board is the at least two generic circuit boards, the inter-board connector or each corresponding one of the plurality of inter-board terminals is joined between corresponding two of the at least two generic circuit boards; 
   a plurality of connector terminals, wherein:
 the at least one connector is one or at least two connectors; 
 each of the at least one connector is provided with a corresponding connector terminal group, which includes at least two connector terminals among the plurality of connector terminals and is configured such that one end portion of each connector terminal included in the corresponding connector terminal group is joined to the end circuit board, and another end portion of each connector terminal included in the corresponding connector terminal group is exposed in the mating bore of a corresponding one of the at least one connector; and 
   at least one connector terminal binder which is made of resin and includes one or at least two connector terminal binders, wherein:   each of the at least one connector terminal binder is provided to a corresponding one of the at least one connector to hold an intermediate portion of each connector terminal included in the corresponding connector terminal group of the corresponding one of the at least one connector and thereby bundle the corresponding connector terminal group of the corresponding one of the at least one connector, or each of the at least one connector terminal binder is provided to adjacent two or more of the at least two connectors to hold the intermediate portion of each connector terminal included in the corresponding connector terminal group of each of the adjacent two or more of the at least two connectors and thereby bundle the corresponding connector terminal group of each of the adjacent two or more of the at least two connectors;   the at least one generic circuit board, to which an end portion of each corresponding one of the plurality of inter-board terminals or a portion of the inter-board connector is joined, is defined as at least one generic circuit board assembly, wherein in the one case where the at least one generic circuit board is the only one generic circuit board, the at least one generic circuit board assembly is only one generic circuit board assembly, and in the another case where the at least one generic circuit board is the at least two generic circuit boards, the at least one generic circuit board assembly is at least two generic circuit board assemblies; and   the end circuit board, to which the one end portion of each of the plurality of connector terminals bound by the at least one connector terminal binder is joined, or additionally another portion of the inter-board connector is joined besides the one end portion of each of the plurality of connector terminals bound by the at least one connector terminal binder, is defined as an end circuit board assembly, the method comprising:   a first process of assembling the at least one generic circuit board assembly to the motor frame, wherein:
 in the one case where the at least one generic circuit board assembly is the only one generic circuit board assembly, which is placed at a lowest one of the plurality of stacking levels, the only one generic circuit board assembly is assembled to the motor frame; and 
 in the another case where the at least one generic circuit board assembly is the at least two generic circuit board assemblies, a lowest one of the at least two generic circuit board assemblies, which is placed at the lowest one of the plurality of stacking levels, is assembled to the motor frame, and a rest of the at least two generic circuit board assemblies is sequentially assembled to the lowest one of the at least two generic circuit board assemblies until a highest one of the at least two generic circuit board assemblies, which is placed immediately below the end circuit board, is assembled; 
   a second process of assembling the end circuit board assembly to the at least one generic circuit board assembly after the first process, wherein:
 in the one case where the at least one generic circuit board assembly is the only one generic circuit board assembly, the end circuit board assembly is assembled to the only one generic circuit board assembly; and 
 in the another case where the at least one generic circuit board assembly is the at least two generic circuit board assemblies, the end circuit board assembly is assembled to the highest one of the at least two generic circuit board assemblies; and 
   a third process of exposing the another end portion of each of the plurality of connector terminals of the end circuit board assembly in the mating bore of the corresponding one of the at least one connector and placing the connector housing to cover the end circuit board assembly and the at least one generic circuit board assembly with the connector housing and fixing the outer tubular portion to the one of the electric motor and the motor frame after the second process, wherein:   the third process is carried out such that a load, which is generated when the another end portion of each of the plurality of connector terminals is exposed in the mating bore of the corresponding one of the at least one connector in the third process, is smaller than a load, which is generated in the first process, and a load, which is generated in the second process.   
     
     
         2 . The method for manufacturing the drive device according to  claim 1 , wherein:
 a bottom of the mating bore of each of the at least one connector has a bottom hole, through which each connector terminal included in the corresponding connector terminal group held by a corresponding one of the at least one connector terminal binder is insertable;   the end circuit board assembly has a hook engaging portion which is provided to a corresponding one of the at least one connector terminal binder or a corresponding one of the plurality of connector terminals and is configured to engage with a hook jig that has a distal end portion shaped in a hook form; and   the third process includes engaging the hook jig to the hook engaging portion at an inside of the bottom hole of a corresponding one of the at least one connector, and lifting the end circuit board assembly toward the connector housing with the hook jig.   
     
     
         3 . A drive device comprising:
 an electric motor which includes a stator and a rotor;   a controller unit which is placed on one side of the electric motor in an axial direction of the electric motor and is configured to control a drive operation of the electric motor, wherein the electric motor and the controller unit are integrally formed together;   a motor frame that is made of metal and is installed to an end portion of the electric motor which faces the controller unit in the axial direction of the electric motor;   at least two circuit boards, each of which holds at least one electronic component of the controller unit and is stacked at a corresponding one of a plurality of stacking levels on an opposite side of the motor frame which is opposite to the electric motor, wherein the at least two circuit boards include:
 an end circuit board which is farthest from the motor frame among the at least two circuit boards; and 
 at least one generic circuit board which is other than the end circuit board; 
   a connector housing that is made of resin and is shaped in a bottomed tubular form and thereby has:
 a top plate portion which is opposed to the end circuit board; and 
 an outer tubular portion which extends from an outer periphery of the top plate portion toward the electric motor and has an end portion fixed to one of the electric motor and the motor frame, wherein the connector housing has at least one connector, and the at least one connector is formed at the top plate portion and has a mating bore which opens toward a side opposite to the end circuit board while a bottom hole opens at a bottom of the mating bore; 
   a plurality of inter-board terminals or an inter-board connector, wherein:
 the at least one generic circuit board is only one generic circuit board or at least two generic circuit boards; 
 in one case where the at least one generic circuit board is the only one generic circuit board, the inter-board connector or each corresponding one of the plurality of inter-board terminals is joined between the only one generic circuit board and the end circuit board; and 
 in another case where the at least one generic circuit board is the at least two generic circuit boards, the inter-board connector or each corresponding one of the plurality of inter-board terminals is joined between corresponding two of the at least two generic circuit boards; 
   a plurality of connector terminals, wherein:
 the at least one connector is one or at least two connectors; 
 each of the at least one connector is provided with a corresponding connector terminal group, which includes at least two connector terminals among the plurality of connector terminals and is configured such that one end portion of each connector terminal included in the corresponding connector terminal group is joined to the end circuit board, and another end portion of each connector terminal included in the corresponding connector terminal group is exposed in the mating bore of a corresponding one of the at least one connector; and 
   at least one connector terminal binder which is made of resin and includes one or at least two connector terminal binders, wherein:   each of the at least one connector terminal binder is provided to a corresponding one of the at least one connector to hold an intermediate portion of each connector terminal included in the corresponding connector terminal group of the corresponding one of the at least one connector and thereby bundle the corresponding connector terminal group of the corresponding one of the at least one connector, or each of the at least one connector terminal binder is provided to adjacent two or more of the at least two connectors to hold the intermediate portion of each connector terminal included in the corresponding connector terminal group of each of the adjacent two or more of the at least two connectors and thereby bundle the corresponding connector terminal group of each of the adjacent two or more of the at least two connectors; and   each of the at least one connector terminal binder covers the bottom hole of the corresponding one of the at least one connector or the bottom holes of the adjacent two or more of the at least two connectors from a side at which the end circuit board is placed, or each of the at least one connector terminal binder is fitted to the bottom hole of the corresponding one of the at least one connector or the bottom holes of the adjacent two or more of the at least two connectors.   
     
     
         4 . The drive device according to  claim 3 , wherein each of the at least one connector terminal binder is resiliently deformed and is fitted to the bottom hole of the corresponding one of the at least one connector. 
     
     
         5 . The drive device according to  claim 3 , wherein in a view taken in the axial direction of the electric motor, the inter-board connector or each of the plurality of inter-board terminals is placed on a radially outer side of the plurality of connector terminals. 
     
     
         6 . A drive device comprising:
 an electric motor which includes a stator and a rotor;   a controller unit which is placed on one side of the electric motor in an axial direction of the electric motor and is configured to control a drive operation of the electric motor, wherein the electric motor and the controller unit are integrally formed together;   a motor frame that is made of metal and is installed to an end portion of the electric motor which faces the controller unit in the axial direction of the electric motor;   at least two circuit boards, each of which holds at least one electronic component of the controller unit and is stacked at a corresponding one of a plurality of stacking levels on an opposite side of the motor frame which is opposite to the electric motor, wherein the at least two circuit boards include:
 an end circuit board which is farthest from the motor frame among the at least two circuit boards; and 
 at least one generic circuit board which is other than the end circuit board; 
   a connector housing that is made of resin and is shaped in a bottomed tubular form and thereby has:
 a top plate portion which is opposed to the end circuit board; and 
 an outer tubular portion which extends from an outer periphery of the top plate portion toward the electric motor and has an end portion fixed to one of the electric motor and the motor frame, wherein the connector housing has at least one connector, and the at least one connector is formed at the top plate portion and has a mating bore which opens toward a side opposite to the end circuit board; 
   a plurality of inter-board terminals or an inter-board connector, wherein:
 the at least one generic circuit board is only one generic circuit board or at least two generic circuit boards; 
 in one case where the at least one generic circuit board is the only one generic circuit board, the inter-board connector or each corresponding one of the plurality of inter-board terminals is joined between the only one generic circuit board and the end circuit board; and 
 in another case where the at least one generic circuit board is the at least two generic circuit boards, the inter-board connector or each corresponding one of the plurality of inter-board terminals is joined between corresponding two of the at least two generic circuit boards; 
   a plurality of connector terminals, wherein:
 the at least one connector is one or at least two connectors; 
 each of the at least one connector is provided with a corresponding connector terminal group, which includes at least two connector terminals among the plurality of connector terminals and is configured such that one end portion of each connector terminal included in the corresponding connector terminal group is joined to the end circuit board, and another end portion of each connector terminal included in the corresponding connector terminal group is inserted through a corresponding one of a plurality of terminal insertion holes formed at a bottom of the mating bore of a corresponding one of the at least one connector and is exposed in the mating bore of the corresponding one of the at least one connector; and 
   at least one connector terminal binder which is made of resin and includes one or at least two connector terminal binders, wherein:   each of the at least one connector terminal binder is provided to a corresponding one of the at least one connector to hold an intermediate portion of each connector terminal included in the corresponding connector terminal group of the corresponding one of the at least one connector and thereby bundle the corresponding connector terminal group of the corresponding one of the at least one connector, or each of the at least one connector terminal binder is provided to adjacent two or more of the at least two connectors to hold the intermediate portion of each connector terminal included in the corresponding connector terminal group of each of the adjacent two or more of the at least two connectors and thereby bundle the corresponding connector terminal group of each of the adjacent two or more of the at least two connectors; and   each of the plurality of connector terminals is fitted to the corresponding one of the plurality of terminal insertion holes formed at the bottom of the mating bore of the corresponding one of the at least one connector through resilient deformation of at least one of: each of the plurality of connector terminals; and the corresponding one of the plurality of terminal insertion holes formed at the bottom of the mating bore of the corresponding one of the at least one connector.   
     
     
         7 . The drive device according to  claim 6 , wherein in a view taken in the axial direction of the electric motor, the inter-board connector or each of the plurality of inter-board terminals is placed on a radially outer side of the plurality of connector terminals.